Dilema: Switch to 95 Octane and retune, or detune" it for regular petrol?

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2nd Hand Yank
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Post by 2nd Hand Yank » Tue Sep 20, 2011 11:06 pm

nachaluva wrote:Yeah i agree it would be waste. I think a tank of 98 octane is all you need for a bit "extra".

Sum1 mentioned "E10"...thats what i use. Its 95 octane & helps support the alternative fuels industry...save the planet! lol :mrgreen:

Plus its 4c/L cheaper than regular unleaded at United servos, plus my shopper docket from IGA (where the community benefits :rolleyes:), thats 8c/L off. Cpl weeks ago i filled up at 133c/L doing this
Main reason I was thinking 95 + octane boost is I have not seen 98 here yet, maybe I haven't looked hard enough, and this would keep the engine from eating itself at low rpm, like starting from a stop in deep sand. For everyday use, I think 95 should prevent virtually all detonation as I don't need to gun-it at low rpm, lol.

Does WA even have United servos?

I've heard rumours that ethanol-mixed petrol actually hurts your fuel economy and power a little, sorta defeating the purpose imho if that's true. Do you notice a difference?

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d_generate
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Post by d_generate » Tue Sep 20, 2011 11:09 pm

I've bought 98 heaps of times over the past 5yrs in Bunbury, one place that sticks in mind is an old BP on a weird shaped block, possibly north of town.
98 Libbo with V3 STI running gear. 13.0 @ 105mph with CAI & 3" Zorst:mrgreen:
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2nd Hand Yank
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Post by 2nd Hand Yank » Wed Sep 21, 2011 9:16 pm

d_generate wrote:I've bought 98 heaps of times over the past 5yrs in Bunbury, one place that sticks in mind is an old BP on a weird shaped block, possibly north of town.
I just spotted it today. :)
Unleaded regular I think is selling for $138.9/L there.
Will go back if I feel I need 98.

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a side effect of 95 vs. 91 octane

Post by 2nd Hand Yank » Wed Sep 21, 2011 9:18 pm

It's harder to start my car when the engine is cold.
Before I could just tap the throttle to engage the choke
and usually it would fire up and keep idling on its own.

I now have to hold my foot over the throttle the first 30-60 seconds
to keep the RPM dropping too low or it will stop the motor.

I'll post more if I see other differences.

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taza
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Post by taza » Wed Sep 21, 2011 9:47 pm

2nd Hand Yank wrote:I just spotted it today. :)
Unleaded regular I think is selling for $138.9/L there.
Will go back if I feel I need 98.
Holly hell $138.9/L is hell cheap. I pay 155.0 :( Or at home $1.70ish for regular.

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NachaLuva
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Post by NachaLuva » Thu Sep 22, 2011 12:05 am

2nd Hand Yank wrote:I've heard rumours that ethanol-mixed petrol actually hurts your fuel economy and power a little, sorta defeating the purpose imho if that's true. Do you notice a difference?
Yeah i've heard that too, plus the rumour that the ethanol eats the seals in the fuel system.

I havent noticed any probs, have good economy & while the power isnt gonna snap any necks lol, its all i expect from a 2.0L.

Dont forget the petrol companies dont make ANY money from ethanol. So its not surprising they would spread rumours! :rolleyes:
d_generate wrote:I've bought 98 heaps of times over the past 5yrs in Bunbury, one place that sticks in mind is an old BP on a weird shaped block, possibly north of town.
Oh no, not BP!

Did you know BP stands for:
Bad Polluter
Bad Petrol
Bl***y Pr**ks
taza wrote:Holly hell $138.9/L is hell cheap. I pay 155.0 :( Or at home $1.70ish for regular.
Damn! Thats pretty expensive.

I've just switched from a gas powered falcon, so i'm used to paying ~50cpl :rolleyes:
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2nd Hand Yank
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Post by 2nd Hand Yank » Thu Sep 22, 2011 1:54 am

taza wrote:Holly hell $138.9/L is hell cheap. I pay 155.0 :( Or at home $1.70ish for regular.
I've seen better in Bunbury. See my earlier posts. :mrgreen:

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2nd Hand Yank
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My car is definitely harder to start cold with 95 octane

Post by 2nd Hand Yank » Fri Sep 23, 2011 9:58 pm

It really does not like idling when the motor hasn't been running in the last 2-3 hrs.
I have to keep my foot on the throttle in the morning for more than 30 seconds, else the motor will just stop itself.
This is with depressing the throttle to enage the auto-choke... still won't idle by itself cold.

Once the motor is half-way to operating temp, no dramas.

Should I do something to make it idle better when it's cold?
I could up the idle speed, but then it would always be using more fuel, even when warm. :???:

*Good thing I didn't buy 98 instead* :mrgreen:

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